Ursa Major (UMa)
"The Great Bear"

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Mythology: The most popular story of Ursa Major links the Great Bear to Bootes, the Herdsman.  This story begins with Zeus' infatuation with a beautiful young woman named Callisto (after which a moon of Jupiter is named), the daughter of King Lycaon of Arcadia.  Callisto was a great hunter and was often in the forest.  As a result, she was a follower of Artemis, Goddess of the Hunt.  As part of her sworn loyalty to Artemis, Callisto took an oath of celibacy.  One day, Zeus learned of the beautiful Callisto and disguised himself as Artemis to approach her.  Upon revealing himself to her, Callisto struggled against him, but to no avail.  Artemis banished Callisto from the forest and Callisto became pregnant with Zeus' child -- Arcas.
    Hera (Zeus' wife) was never pleased with Zeus' infidelities, and often took her jealousy out on Zeus' "conquests."  Because of this, Hera turned Callisto into a bear.
    Later, King Lycaon invited Zeus to dinner.  To test Zeus, Lycaon had Arcas cut up and served as a meal to the Olympian God.  When he realized what had happened, Zeus killed the sons of Lycaon with his thunderbolts and then turned Lycaon into a wolf.  Zeus gathered the pieces of Arcas and reassembled them.  Arcas was given to the Pleaide Maia to be raised.  Later, when Arcas had grown, he was out hunting and stumbled across the bear that was his mother, Callisto.  The bear ran to the temple of Zeus, with Arcas following her in an attempt to slay the bear.  Upon reaching the temple, Zeus brought both of them to the sky -- Callisto became Ursa Major, the Great Bear, and Arcas became the Bear Herder, Bootes.  (So why does the Bear have a long tail?  One version of the story claims that the Gods drug Ursa Major to the sky by her tail, stretching it and making it long!)
    A happy ending, with mother and son united in the stars?  Not quite:  Ursa Major is a circumpolar constellation; that is, it never rises nor sets as seen from Northern latitudes -- it just goes around in circles.  This was arranged by Hera -- the Bear will never drink nor bathe since it cannot get to Earth (set) and the water.

Note:  The asterism of the Big Dipper lies within Ursa Major; the handle of the Big Dipper is the long tail of the Bear.  The Big Dipper is probably the most famous star picture there is, and often the first thing people look for when stargazing since it is visible all year (at least in the United States).  The two stars that make up the end of the cup of the Big Dipper, Dubhe and Merak, are called "pointer stars" and point the way to Polaris, the North Star.  This trick has been used for centuries -- long before the compass was invented!

Interesting Trivia:  The second point in the handle of the asterism of the Big Dipper is actually two stars -- Mizar and Alcor.  These stars make a visual binary -- they appear to be next to each other in space only because they lie within the same line of sight (actually, both Mizar and Alcor are true binaries themselves!).  The eye test to be a Roman soldier was to be able to distinguish between these two stars.  If you want to see if your eyesight is good enough so that you could have been a Roman soldier, a trick to viewing Mizar and Alcor is to look a little to one side of them.  This trick is called "averted vision" and allows the light to fall on the more sensitive rods in your eyes.

Other Interesting Sights:  The Giant Pinwheel Galaxy, M101 (NGC5457) is in Ursa Major.  This galaxy, which is 24 million light-years away and 90,000 light-years across, is magnitude 8, meaning it is just beyond the brightness range of our eyes.  It is the largest galaxy in a local group; in fact, it is so large that its gravity is having a shearing effect on the other galaxies in that group!